Triazoles Synthesis & Applications as Nonsteroidal Aromatase Inhibitors for Hormone-Dependent Breast Cancer Treatment

In the last few years, nonsteroidal aromatase inhibitors (AIs) have been emerged as promising agents for treating hormone-dependent breast cancer in postmenopausal women because of their inhibitory effect on estrogen synthesis. Indeed, these compounds can block the activity of aromatase, the enzyme that intervenes in the last steps of estrogen production pathway. Triazoles are the core structures of nonsteroidal AIs. The nitrogen atom of the triazole moiety plays a fundamental role in the aromatase functionality by interacting with the iron ions of the heme group. In general, AIs possess numerous advantages as they quench the last step of estrogen synthesis without any inhibitory effects on the production of other steroids produced via the same pathway. Some AIs as anastrozole, letrozole, and vorozole have already been approved by the Food and Drug Administration in the treatment of breast cancer. The previously mentioned compounds present severe and adverse effects as polycystic ovary syndrome (PCOS), resistance onset on long-term treatments, and a higher risk of bone fractures. This review focuses intensively on the role of AIs in the treatment of hormone-sensitive types of cancers, especially the role of triazoles as nonsteroidal AIs. Also, the review provides an overview about the chemistry of triazoles along with the different methods by which the $v$ -triazoles and s-triazoles are synthesized.

Potential Herb-Drug Interactions in the Management of Age-Related Cognitive Dysfunction

Late-life mild cognitive impairment and dementia represent a significant burden on healthcare systems and a unique challenge to medicine due to the currently limited treatment options. Plant phytochemicals have been considered in alternative, or complementary, prevention and treatment strategies. Herbals are consumed as such, or as food supplements, whose consumption has recently increased. However, these products are not exempt from adverse effects and pharmacological interactions, presenting a special risk in aged, polymedicated individuals. Understanding pharmacokinetic and pharmacodynamic interactions is warranted to avoid undesirable adverse drug reactions, which may result in unwanted side-effects or therapeutic failure. The present study reviews the potential interactions between selected bioactive compounds (170) used by seniors for cognitive enhancement and representative drugs of 10 pharmacotherapeutic classes commonly prescribed to the middle-aged adults, often multimorbid and polymedicated, to anticipate and prevent risks arising from their co-administration. A literature review was conducted to identify mutual targets affected (inhibition/induction/substrate), the frequency of which was taken as a measure of potential interaction. Although a limited number of drugs were studied, from this work, interaction with other drugs affecting the same targets may be anticipated and prevented, constituting a valuable tool for healthcare professionals in clinical practice.

Analysis of Bioactive Amaryllidaceae Alkaloid Profiles in Lycoris Species by GC-MS

The genus Lycoris, a group of Amaryllidaceae plants distributed in temperate regions of Eastern Asia, is already known for containing representative alkaloids typical of this botanical family with a wide range of biological activities (for example, lycorine and galanthamine). In the present work, the alkaloid profiles of nine species, L. albiflora, L. aurea, L. chinensis, L. haywardii, L. incarnata, L. longituba, L. radiata, L. sprengeri, and L. squamigera, and one variety ( L. radiata var. pumila) have been evaluated by GC-MS. Structures belonging to the lycorine-, homolycorine-, haemanthamine-, narciclasine-, tazettine-, montanine- and galanthamine-series were identified and quantified, with galanthamine- and lycorine-type alkaloids predominating and usually showing a high relative abundance in comparison with other alkaloids of the extracts. Interestingly, L. longituba revealed itself to be a potential commercial source of bioactive alkaloids. In general terms, our results are consistent with the alkaloid profiles reported in the literature for previously studied species.

Cytotoxic Agents of the Crinane Series of Amaryllidaceae Alkaloids

In the alkaloid galanthamine, the plant family Amaryllidaceae has endowed the pharmaceutical community with a potent and selective inhibitor of the enzyme acetylcholinestersae (AChE), of prominence in the chemotherapeutic approach towards motor neuron diseases. Following on the commercial success of this prescription drug in the treatment of Alzheimer's disease, it is anticipated that other drug candidates will in future emerge from the family. In this regard, the phenanthridones, exemplified by narciclasine and pancratistatin, of the lycorine series of Amaryllidaceae alkaloids have shown much promise as remarkably potent and selective anticancer agents, with a drug target of the series destined for the clinical market within the next decade. Given these interesting biological properties and their natural abundance, plants of the Amaryllidaceae have provided a diverse and accessible platform for phytochemical-based drug discovery. The crinane series of Amaryllidaceae alkaloids are also enriched with a significant array of biological properties. As a consequence of their close structural similarity to the anticancer agents of the lycorine series, the cytotoxic potential of crinane alkaloids has been realized through structure-activity relationship (SAR) studies involving targets of both semi-synthetic and natural origin, which has identified several members as leads with promising antiproliferative profiles. As the first of its kind, this review seeks to collate such information from the past few decades in advancing the crinane group as a viable platform for anticancer drug discovery.

Cytotoxic Agents of the Crinane Series of Amaryllidaceae Alkaloids

In the alkaloid galanthamine, the plant family Amaryllidaceae has endowed the pharmaceutical community with a potent and selective inhibitor of the enzyme acetylcholinestersae (AChE), of prominence in the chemotherapeutic approach towards motor neuron diseases. Following on the commercial success of this prescription drug in the treatment of Alzheimer's disease, it is anticipated that other drug candidates will in future emerge from the family. In this regard, the phenanthridones, exemplified by narciclasine and pancratistatin, of the lycorine series of Amaryllidaceae alkaloids have shown much promise as remarkably potent and selective anticancer agents, with a drug target of the series destined for the clinical market within the next decade. Given these interesting biological properties and their natural abundance, plants of the Amaryllidaceae have provided a diverse and accessible platform for phytochemical-based drug discovery. The crinane series of Amaryllidaceae alkaloids are also enriched with a significant array of biological properties. As a consequence of their close structural similarity to the anticancer agents of the lycorine series, the cytotoxic potential of crinane alkaloids has been realized through structure-activity relationship (SAR) studies involving targets of both semi-synthetic and natural origin, which has identified several members as leads with promising antiproliferative profiles. As the first of its kind, this review seeks to collate such information from the past few decades in advancing the crinane group as a viable platform for anticancer drug discovery.